Humidifier



p l 30, 1940- F. W.)STILWELL 2.198.890

HUMIDIFIER 1 Filed Nov 2, 19:58 6 Sheets-Sheet 1 fza/zzal or 1 520 [a Sill /ell )xedmf/ yw we. i

April 30, 1940. E. w. QTILWELL .HUMIDIFIER Filed Nov. 2, issa 6 Sheets-Sheet 2 April 30, 1940. F. w. STILWELL HUMIDIFIER 6 Sheets-Sheet 3 A Na n; wezzzwzz v g g: z ag zfm April 30, 1940.

F. w. ,STILWELL 2.198.890

HUMIDIFIER Filed Nov. 2, 1938 e Sheets-Sheet 4 ,m mm

Ap 30, 1 STILWELL 2,198,890 I UNI E STATES; Paras-r. oer-ice me w. sumo. came. m. Application November '2, 1988, Serial 80. $88,198,

5 Claims- (01. sci- 1s my invention relates to humidifiers and is more particularly concerned with a humidifier adapted to be installed in an office, home, or similar en!- vironment.

5 The humidifiers now' on the market for installation in homes and offices are objectionable in that they lack the necessary nicety of control, with the result that they provide over-humidification. A further and even more serious dit- 1'0' fieulty with present humidifiers of this. type lies in the fact that they are apt to overflow and damage rugs, floors, plaster, wall paper, and other household and office furnishings and appoint.- ments. I

15 A primary object of my invention is to overcome these difilculties of the prior art humidifiers.

Another object of my invention is to provide a humidifier having an evaporator providing a go maximum evaporating surface with a minimum volume of water.

Another object of my invention is to provide a humidifier having an improved control mechanism whereby the humidification may be ac- 2a curately and nicely controlled to provide exac the degree of humidity desired.

Another object of my invention is to provide a humidifier having an improved control mechanism which will absolutely prevent overflow and so resultant'damage to floors, ceilings, walls and fur-v Another object of my invention is to provide a humidifier having an electric booster for increasing the temperature of the water in the evapogs rater.

Another object of my invention is to, provide a humidifier which may also be used as a heater for incr the temperature of the air in the room or building in which the humidifier is 10- an cated.

Another object or my invention is to provide a neat, attractive; inexpensive, and compact hiimidifier for oihces and d.

Another object of my invention is to provide a I & humidifier which may be automatically controlled line 1-1 of Figure 4';

securing means.

Figure 3 is an-irregular lineS-Iofl'igure2;

Figureiisapartialvertical section showing the control 111 and is taken on the line W 4-4 of Figure 3; a

Figure 51s a partial sectionshowing the emergency'control mechanism and is taken on the lineHofFlsure4; 4

Figurefiisapartial'viewottheregularcontrol mechanism for maintaining the proper water 10 level in the evaporator and is'taken on the line 6-8 ofFlgure4;

Figure '7 shows a detail of the emergency controlmechanismandistahenontheirregular" Figureaisawiringdlagram;

Fisure9isapsrtialwiringdiagramof amodlfled iormof my invention;

Figure 10 is a top plan view of a modified form of my invention wherein I have provided a heating element for raising the room temperature, most of the top of the cabinet being removed to showthe internal construction; and I Figure 11 is a partial vertical section of the modification of Figure 10 and is taken on the line ll-H of Figurelo.

Referring to Figures 1 to 8 of the drawings, I have shown therein an embodiment of my invention comprising a cabinet indicated generally by the reference numeral [2 and comprising a 30 base M mounted on adjustable feet I! and a top l8 supported on the base M. The cabinet is preferably made of sheet metal or other suitable material and may be provided with any attractive and suitable finish.

The evaporator indicated generally by the reference numeral 20 comprises a pan 2! having upwardly extending flanges 24 secured to the walls of the top It by bolts, welding, or other suitable This pan 22 has a depressed central portion 26 between edge portions 28 and 30. As most clearly shown in Figure 3, the pan 22 extends from one end of the cabinet H to a partition 32 which divides the top portion it of the cabinet into an evaporator compartment 34 and a control compartment It, the partition 32 being located adjacent one end of the cabinet, so that the evaporator compartment 34 extends for almost the full length of the cabinet.

Hie evaporator pan 22 is adapted to contain water to the level indicated in Figure 2 and the depressed central portion 2' contains the heating pipes 38 which extend lengthwise .of the pan 22; as most clearly shown in Figure 3, and cause the heating medium to flow baclrand forth lengthwise of the evaporator pan. These heating pipes 36 have an inlet 66 and an outlet 62 adapted to be connected with the steam or hot water pipes for heating the building. in which my humidifier is installed.

' Where the heating pipes 66 are connected with a hot water heating system wherein the temperature of the hot water supply is insufficient to provide the desired amount of heat for the water in the humidifying pan 22 I provide a heat booster.inlthe -form jof an electrical heatingwelementll' locatedin the central depression 26 below the heating pipes 66, as most clearly indicatedin Figure 2. Where the heat supplied to the water in the evaporator pan 22 by means of the heating It will be noted that this evaporator provides a surface which extends the full width of the cabinet and substantially the full length thereof, thus providing a maximum surface for evaporation. This full surface is exposed to the circulation of air through the top portion I6 of the cabinet. This air enters'through the inlet 66 at the back of the cabinet and after picking up the moisture evaporated from the surface of the water in the pan 22, the humidified air leaves the cabinet by way of the grille 56.

By referring to Figures 2 and 3, it will be noted that the water level maintained by control mechanism to be hereinafter described, is such that only a thin film of water overlies the sides 26 and 66 of the evaporator pan 22 and that there is only a small amount of water in the depressed central portion 26 of this pan, due to the fact that the greater portion of the volume of this central portion of the pan is occupied by the heating pipes 66. This is an important feature of my invention in that it makes possible accurate control of the humidity of the room in which the unit is located. In order to further decrease the amount of water in the evaporator pan 22, I may fill most or all of the available space in the evaporator pan up to the level of the water therein with copper shavings 62 or other suitable non-corrosive heat conducting material providing interstices which are filled by the water in the evaporator pan.

Water is supplied to the evaporator pan 22 by way of a pipe 66 which is connected to the water pipes of the building in which the humidifier is installed. As best shown in Figure 4 this pipe 66 is provided with a normally opened valve 66 and a normally closed solenoid controlled valve 68. The regular water level control. float 66 is located in a corner of the central portion 26 of the evaporator pan which is not occupied by the heating pipes 66 or the copper shavings 62. This float has a rod 62 extending through the opening provided by a guide 66 attached to the partition 32. The upper end of the rod 62 is connected to one end of a lever 66 extending through the partition 32 and pivoted at 66011 a bracket I6 at-' tached to the partition 62. The other end of the lever 66 carries a mercury switch I2 which con- In the drawingsI havetrols the circuit containing the-solenoid valve 66.

This solenoid valve 66 is normally closed, thereby cutting off the supply of water to the evaporator pan 22. When the water level in this pan drops below a predetermined level, the float 66 pulls downwardly on the right-hand end of the lever 66 as viewed in Figure 6 and shifts this lever about its pivot 66 so that the mercury in the bulb of the switch I2 closes a circuit between the switch contacts and thus closes the circuit including the solenoid valve .66.; ,--The resultant ""erie'rg i'zation of the solenoid control for this valve opens the valve and permits water to flow through "the pipe 66 to the evaporator pan 22.

water level in the evaporator pan 22 reaches the When the desired maximum level, the float 66 shifts the lever 66 in the opposite direction, thereby opening the mercury switch 12 and thus cutting oi! the supply of current to the solenoid control of valve 66. This valve thereupon closes and cuts of! the supply of water to the evaporator pan.

One of the principal disadvantages with prior art humidifiers of this general type has been the failure of such control mechanism with resultant overflow and damage to walls, floors, plaster, and furnishings. A feature of my invention lies in an emergency control mechanism which prevents such overflow in case of failure of the normal control mechanism.

I have illustrated my improved humidifier as being provided with a large emergency float I6 which normally rests on the heating pipes 66. This float I6 is connected to one end of a lever I6 extending through the partition 62 and pivoted at I6 on a block 66 attached to this partition. The other end of the lever I6 is in the form of a trigger 62 engaged in the notch 66 of a lever 66. Thisengagement of the trigger 62 in the notch 64 prevents the lever 66 from rotating about its pivot 66 under the influence of spring 66.

If the regular control mechanism operated by the float 66 should for any reason fail to cut off the supply of water and the water in the pan 22 should rise above the permissible maximum level, the rising water would raise the emergency float I6, thus releasing the trigger 62 from the notch 66. The lever 66 would thereupon rotate about its pivot 66 under the pull of the spring 66. This lever 66 'carries a pair of. pins 62 adapted to engage opposite sides of the control arm 66 of valve 66 so that the pivotal movement of the lever 66 under the influence of spring 66 closes valve 66 and cuts off the supply of water to the evaporator pan 22.

The lever 66 also has a pin 66 extending through the U-shaped member 66 attached to the lower end of a switch control rod I66 pivotally attached to links.l62 and I66 pivotally supported on brackets I66 and I 66 respectively, these brackets being attached to the partition 62. The switch control rod I66 carries a second U- shaped member II6 which embraces the trigger control II2 of switch Ill which cuts ofl the supply of current to the heating unit 66 and the solenoid control valve 66.

I preferably provide my humidifier with automatic means for regulating the humidity in the room in which my humidifier is installed. This automatic humidity control comprises a humidostat II6 illustrated as mounted on the front of the cabinet just above the electrical'heating element control switch 66. This humidostat controls a relay 6 in series with the solenoid controlled valve 66 so that no current can be proaiaasao vided to open the valve and thus admit water to the pan 22unless additional'humidity is called 'for' by the humidostat IIS.

From the foregoing, it will be apparent that as soon as the humidity in the room reaches the r desired maximum, the humidostat IIB operates the relay II. to break the circuit containing the solenoid controlled valve 50 and thus cuts on the there is only a very'slight amount of water in theevaporator which will thereafter be vaporized and this small amount of water will not'appreeiably increase the humidity in the room after the desired humidity has been reached. This provides a nicety of control which is lacking in the prior art. and which is a great improvement thereover. g

I have provided my humidifier with a drain pipe I to permit draining of the evaporator pan 22 whenever desired. This drain pipe I20 is controlled by' a manually operated valve I22 (Figure 11) which can be reached through a door I24 (Figure 1) located atone end of the cabinet I2. The opposite end of the cabinet is provided with a second door I26 (Figure 3) to provide access to the control compartment 00.

In the embodiment of Figures 1 to 8 inclusive, the relay H8 is also in series with the electrical heating coil 44 so that the current supplied to this coil 44 is automatically cut of! when humid- --ity in the room reaches the desired maximum.

In this embodiment, however, I have provided no means for cuttingofl' the supply of heat to the heating pipes 38, although I appreciate that in some installations the heat supplied to these pipes may be under the control of a thermostat regulating the entire heating system of the building in which the installation is made.

In Flgure'9 I have indicated a modificationin which the pipe I28 through which steam, hot

water, or other heating medium is supplied to the heating pipes 28 is provided with a valve I30 normallyclosed by a spring I32. The valve I30 is opened by a solenoid I34 under the control of the humidostat I I6 and relay 8. In this particular embodiment the heating coil 44 and heating pipes 38 are adapted to be used alternately under the control of the manually operated switch 46.

In the embodiment of Figures 10 and 11 I have illustrated a further modification wherein the heating pipes 28 are provided with inlet and outlet T's 40a and 42a in lieu of the elbows illustrated in Figure 3. The T 40a is connected to a hot water or steam supply pipe I38 and the r 42a is connected to a hot water or steam return pipe I38.

In this embodiment of my invention I have illustrated a heating unit indicated generally by reference numeral I40 as being located above the evaporator 20. The purpose of this heating unit I40 is to heat the air passing through the humidifier and thus heat the room to the desired temperature. A humidifier having such a heating unit may be used to replace the usual radiator.

The heating unit I40 comprises an inlet header I42 connected by'thepipe I44 to the T 4041 and an outlet header I46 connected by pipe I 48 to T 42a. The inlet header I42 is connected by three parallel pipes I50 to a transfer header I52 which communicates with the parallel pipes I54 leading to the outlet header I46. The pipes 6% and I54 are preferably provided with sheet metal iins I56 to facilitate transfer of heat to the air passing over and around the pipes I50 and the. V

The heating unit I40 is carried on the pipes it and I48 and the U-shaped support I58 located beneath the header I52. In Figure 10 I have shown this heating unit I40 as being materially shorter than the evaporator 20 but it is to be understood that the heating unit I40 may be made of any desired and suitable length and provided with any desired number of pipes I50 and IM. The heating unit I40 may also be made of less width than the cabinet It.

My humidifier is adapted to be connected into the'electric lighting circuit of the oflice or home in which it is located. In the drawings I have illustrated my humidifier as being provided with a conventional flexible electric cord I60 which is detachably connected to the humidifier by the conventional plug and socket connection I62. I have also provided my humidifier with a manually controlled master switch I04.

In the drawings Ihave illustrated an attractive and desirable shape for my humidifier or combined humidifier and heater. It will be understood, however, that my invention is not limited to the particular shape shown or the details herein illustrated and described as my invention may assume various other forms and shapes. It will be further understood that my invention may be made in various sizes and designs for different purposes and different sizes of rooms, apartments, or buildings to conform to the various needs thereof. It will be also understood that my humidifier may be used to humidity only a single room or a group of rooms or an entire building.

I claim:

1. A humidifier for use in a heating circuit adapted to continue in operation independently of humidity conditions comprising a cabinet for location in a room of a home or ofiice building, an evaporator pan mounted in said cabinet, said evaporator pan having a relatively deep central portion and shallow side portions, means for supplying water to said evaporator pan, heat exchange means-substantially filling the deep central portion of said evaporator pan and adapted to be surrounded ,by water therein, said heat exchange means being connected in the heating circuit and supplied therefrom regardless of the presence or absence of water in said evaporator pan, a float control 'for cutting off the supply of water to said pan when a predetermined water level obtains in said pan, said level being only slightly above the bottoms of the shallow side portions and providing a thin sheet of water thereover, and a humidostat control for cutting off the supply of water to said pan when a predetermined humidity obtains, said cabinet providing an entrance and exit for air passing over said evaporator pan.

2. A humidifier for use in a heating circuit adapted to continue -in operation independently of humidity conditions comprising a cabinet for location in a room ofa home or oflice building, an evaporator pan mounted in said cabinet, said evaporator pan having a relatively deep central portionand shallow side portions, means for supplying water to said evaporator pan, heat exchange means substantially filling the deep central portion of said evaporator pan and adapted to be surrounded by water therein, said heat exchange means being connected in the heating circuit and supplied therefrom regardless of the presence or absence of water in said evaporator pan, a float control for cutting oi! the supply water to said pan when a predetermined water level obtains in said Dan, said level being only slightly above the bottoms of the shallow side portions and providing a thin sheet of water thereover, an, additional heat exchange means mounted in said cabinet above said evaporator pan, said last-named heat exchange means being connected to said heating circuit and supplied therefrom, and a humidostat control for cutting on the supply 01' water to said pan when a predetermined humidity obtains, said cabinet providing an entrance and exit for air passing over said evaporator pan and additional heat exchange means.

3. A humidifier for use in a heating circuit adapted to continue in operation independently of humidity conditions comprising a cabinet for location in a room of a. home or ofllce building, an evaporator pan mounted in said cabinet, said evaporator pan having a relatively deep central portion and shallow side portions, means for supplying water to said evaporator pan, heat exchange means substantially filling the deep central portion of said evaporator pan and adapted to be surrounded by water therein, said heat exchange means being connected in the heating circuit and supplied therefrom regardless of the presence or absence of water in said evaporator pan, a float control for cutting oil the supply of water to said pan when a predetermined water level obtains in said pan, said level being only s ightly above the bottoms'of the shallow side portions and providing a thin sheet of water thereover, an electric heater mounted insaid evaporator pan, and a humidostat control for cutting oil the supply of water to said pan and the current to said electric heater when a predetermined humidity obtains, said cabinet providing an entrance and exit for air passing over said evaporator pan.

4, A humidifier for use in a heating circuit adaptedto continue in operation independently of humidity conditions comprising a cabinet for location in a room of a home or oflice building, an evaporator pan mounted in said cabinet, said evaporator pan having a relatively deep central circuit and supplied therefrom, regardless oi the presence or absence or water in said evaporator pan, a float control for cutting oi! the supply of water to said pan when a predetermined water level obtains in said pan, said level being only S ightly above the bottoms of the shallow side portions and providing a thin sheet 01' water thereover, a vfiller oi high heat conductivity i'or said pan, said filler having interstices adapted to be fllled by water in said pan, and a humidostat control for cutting of! the supply 01' water to said pan when a predetermined humidity obtains, said cabinet providing an entrance and exit for air passing over said evaporator pan.

5.' A humidifier for use in a heating circuit adapted to continue in operation independently of humidity conditions comprising a cabinet for location in a room. 01' a home or oflice building, an evaporator pan mounted in said cabinet, said evaporator pan having a relatively deep central portion and shallow side portions, means for supplying water' to said evaporator pan, heat exchange means substantially filling the deep central portion 01' said evaporator pan and adapted to be surrounded by water therein, said heat exchange means being connected in the heating circuit and supplied therefrom regardless oi! the presence or absence of water in said evaporator pan, a float control for cutting oil the supply of water to said pan when a predetermined water level obtains in said pan, said level being only slightly above the.bottoms oi the shallow side portions and providing a thin sheet of water thereover, emergency control means for cutting oflf the supply of water to said pan upon failure of said float control, and a humidostat control for cutting of! the supply of water to said pan when a predetermined humidity obtains, said cabinet providing an entrance and exit for air passing over said evaporator pan.

FREDW. STILWEIL. 

